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Journal of Analysis and Testing 2021年第3期5卷 225-234页

作者： zheng-fen pu Bi-Chao Wu Yuan-Hang Tan Qiu-Lin Wen Jian Ling Qiu-E Cao Functional Molecules Analysis and Biotransformation Key Laboratory of Universities in Yunnan Province School of Chemical Science and TechnologyYunnan UniversityKunming 650091China

In this study,we established a simple colorimetric method for visual detection of chromium(Ⅲ)ions using aggregated silver nanoprisms induced by monohydrogen *** detection strategy had two steps,selective aggregation of silver nanoprisms with monohydrogen phosphate at high temperature,and anti aggregation of silver nanoprisms in the presence of chromium(Ⅲ)*** this strategy,significant spectral shift of the localized surface plasmon resonance(LSPR)absorption peak of silver nanoprisms could be visualized with the color changed from yellow to *** spectral peak shift of silver nanoprisms in the anti-aggregation process was linear with the concentrations of the added chromium(Ⅲ)ions in the range of 20.0-800.0 ***,a colorimetric method for chromium(Ⅲ)ions detection was established with the detection limit of 3.6 *** experimental results of real water samples indicated that the colorimetric sensor was potential in environmental monitoring.

关键词： Silver nanoprisms Aggregation Chromium Localized surface plasmon resonance Monohydrogen phosphate

NOX4 exacerbates Parkinson's disease pathology by promoting neuronal ferroptosis and neuroinflammation

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Neural Regeneration Research 2025年第7期20卷 2038-2052页

作者： Zhihao Lin Changzhou Ying Xiaoli Si Naijia Xue Yi Liu Ran zheng Ying Chen Jiali pu Baorong Zhang Department of Neurology The Second Affiliated HospitalZhejiang University School of MedicineHangzhouZhejiang ProvinceChina

Parkinson's disease is primarily caused by the loss of dopaminergic neurons in the substantia nigra ***,a novel form of regulated cell death characterized by iron accumulation and lipid peroxidation,plays a vital role in the death of dopaminergic ***,the molecular mechanisms underlying ferroptosis in dopaminergic neurons have not yet been completely *** oxidase 4 is related to oxidative stress,however,whether it regulates dopaminergic neuronal ferroptosis remains *** aim of this study was to determine whether NADPH oxidase 4 is involved in dopaminergic neuronal ferroptosis,and if so,by what *** found that the transcriptional regulator activating transcription factor 3 increased NADPH oxidase 4 expression in dopaminergic neurons and astrocytes in an 1-methyl-4-phenyl-1,2,3,6 tetrahydropyridine-induced Parkinson's disease *** oxidase 4 inhibition improved the behavioral impairments observed in the Parkinson's disease model animals and reduced the death of dopaminergic ***,NADPH oxidase 4 inhibition reduced lipid peroxidation and iron accumulation in the substantia nigra of the Parkinson's disease model ***,we found that NADPH oxidase 4 interacted with activated protein kinase Cαto prevent ferroptosis of dopaminergic ***,by lowering the astrocytic lipocalin-2 expression,NADPH oxidase 4 inhibition reduced 1-methyl-4-phenyl-1,2,3,6 tetrahydropyridine-induced *** findings demonstrate that NADPH oxidase 4 promotes ferroptosis of dopaminergic neurons and neuroinflammation,which contribute to dopaminergic neuron death,suggesting that NADPH oxidase 4 is a possible therapeutic target for Parkinson's disease.

关键词： dopaminergic neuron ferroptosis NADPH oxidase 4(NOX4) neuroinflammation Parkinson's disease

[Determination of 12 halogenated organic pollutants in edible fish by ultra performance liquid chromatography-high resolution mass spectrometry combined with ultrasound-assisted extraction and gel permeation chromatography purification]

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Se pu = Chinese journal of chromatography 2025年第1期43卷 68-77页

作者： Yi-Zhe Zhu Rui-fen zheng Zi-Hao Fan Ling Liu Jing-Yao Ye Kai Wang Cai-Ming Tang Research Center for Eco-Environmental Engineering Dongguan University of Technology Dongguan 523808 China. Guangdong Key Laboratory of Environmental Resources Utilization and Protection Guangzhou Institute of Geochemistry Chinese Academy of Sciences Guangzhou 510640 China.

Halogenated organic pollutants (HOPs) have attracted considerable attention owing to their persistence, bioaccumulation, and toxicity. The development of methods to detect HOPs in fish is challenging owing to the compositional complexity of fish matrices, which contain high levels of lipids and relatively low concentrations of HOPs. In addition, the lipophilicity of most HOPs renders their extraction difficult. Moreover, the simultaneous determination of multiple HOPs to achieve the high-throughput screening of these analytes is complex. In this study, a reliable and efficient pretreatment method based on ultrasound-assisted extraction, gel permeation chromatography purification, and ultra performance liquid chromatography-high resolution mass spectrometry (UPLC-HRMS) was developed for the determination of 12 HOPs in edible fish. The procedures of sample extraction and purification and LC-HRMS detection parameters were optimized to improve the performance of the method. Fresh fish samples were thoroughly rinsed with water, and non-edible parts, including the skin, bones, and phosphorus, were removed. The fish were weighed, cut into small pieces, and vacuum freeze-dried for 48 h. Subsequently, a freeze grinder was used to grind the dried fish into a fine powder. Exactly 2 g of the fish powder was weighed, fortified with isotope-labeled internal standards of the HOPs, and allowed to stand for 5 min. Methanol-acetonitrile (1∶1, v/v) was then added, followed by vortex mixing and ultrasonication. After centrifugation, the supernatant was transferred to a fresh tube. The extraction process was repeated twice and all extracts were combined. The extract was evaporated under a gentle nitrogen flow and redissolved in a mixture of ethyl acetate-cyclohexane (1∶1, v/v). The sample mixture was cleaned using gel permeation chromatography, and the eluate was collected and concentrated under a nitrogen flow. Sample residuals were reconstituted with water-methanol (1∶1, v/v) prior to

关键词： edible fish gel permeation chromatography (GPC) halogenated organic pollutants (HOPs) ultra performance liquid chromatography-high resolution mass spectrometry (UPLC-HRMS)

Luminescence of samarium doped hydroxyapatite containing strontium:Effects of doping concentration

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Journal of Rare Earths 2022年第3期40卷 398-405,I0002页

作者： pu Chen fen Wang Yinpo Qiao Zhen Zhang Shaanxi Key Laboratory of Green Preparation and Functionalization for Inorganic Materials School of Materials Science and EngineeringShaanxi University of Science and TechnologyXi'an 710021China

A series of samarium(Sm)doped hydroxyapatites containing strontium(Sr)with controllable and adjustable luminescence were designed and prepared via chemical hydrolysis co-precipitation *** effects of doping concentration of Sm on the structure,composition,photoluminescence(PL),energy transfer,substitute site,fluoresce lifetime and luminescence color of samples were *** is shown that the introduction of Sr ions induces the structure and composition change for Sm doped *** typical transitions of Sm^(3+) at 564,601,648 and 707 nm due to^(4)G_(5/2)→^(6)H_(J/2)(J=5,7,9 and 11)transition under the excitation of 404 nm were *** PL intensity is affected by the Sr/Ca ratio and Sm concentration,and the optimal concentration of Sm is 0.8 mol%when Sr/Ca ratio equals 7/*** non-radiative transitions and energy transfer of Sm ions are the main reason for the quenching,and the interactions among ions are ascribed to dipole-dipole type by theoretical ***,the ratio of PL intensity between 601 and 648 nm(r_(O/R)=I_(601nm)/I_(648nm))indicates the symmetry and substitution process of Sm ions to Ca/Sr *** fluorescence lifetime(τ)decreases with the concentration of Sm increasing,which is the result of the decrease of distance and the enhanced interaction between Sm *** CIE chromaticity coordinates and luminescence color of samples are in the orange-red region and have close relation with the concentration of ***,the cytotoxicity evaluation and confocal laser scanning microscopy(CLSM)observation of samples via cells indicate the good biocompatibility and safe use of this kind of bio-based luminescent materials for their potential efficient fluorescence labeling and detection.

关键词： Samarium Strontium Hydroxyapatite Photo-luminescence Energy transfer Cytotoxicity evaluation

Effect of Vegetation Changes on Soil Erosion on the Loess Plateau

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Pedosphere 2006年第4期16卷 420-427页

作者： zheng fen-Li State Key Laboratory of Soil Erosion and Dryland Farming in Loess Plateau Northwest A＆F University Yangling 712100 （China）.

Vegetation is one of the key factors affecting soil erosion on the Loess Plateau. The effects of vegetation destruction and vegetation restoration on soil erosion were quantified using data from long-term field runoff plots established on the eastern slope of the Ziwuling secondary forest region, China and a field survey. The results showed that before the secondary vegetation restoration period (before about 1866-1872), soil erosion in the Ziwuling region of the Loess Plateau was similar to the current erosion conditions in neighboring regions, where the soil erosion rate now is 8000 to 10000 t km-2 year-1. After the secondary vegetation restoration, soil erosion was very low; influences of rainfall and slope gradient on soil erosion were small; the vegetation effect on soil erosion was predominant; shallow gully and gully erosion ceased; and sediment deposition occurred in shallow gully and gully channels. In modern times when human activities destroyed secondary forests, soil erosion increased markedly, and erosion rates in the deforested lands reached 10000 to 24000 t km-2 year-1, which was 797 to 1682 times greater than those in the forested land prior to deforestation. Rainfall intensity and landform greatly affected the soil erosion process after deforestation. These results showed that accelerated erosion caused by vegetation destruction played a key role in soil degradation and eco-environmental deterioration in deforested regions.

关键词： deforestation Loess Plateau natural vegetation restoration soil erosion

Effects of Accelerated Soil Erosion on Soil Nutrient Loss After Deforestation on the Loess Plateau

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Pedosphere 2005年第6期15卷 707-715页

作者： zheng fen-Li State Key Laboratory of Soil Erosion and Dryland Farming in Loess Plateau Institute of Soil and Water ConservationChinese Academy of Sciences and Ministry of Water Resources Yangling 712100 （China）

Soil erosion and nutrient losses on newly-deforested lands in the Ziwuling Region on the Loess Plateau of China were monitored to quantitatively evaluate the effects of accelerated soil erosion, caused by deforestation, on organic matter, nitrogen and phosphorus losses. Eight natural runoff plots were established on the loessial hill slopes representing different erosion patterns of dominant erosion processes including sheet, rill and shallow gully (similar to ephemeral gully). Sediment samples were collected after each erosive rainfall event. Results showed that soil nutrients losses increased with an increase of erosion intensity. Linear relations between the losses of organic matter, total N, NH4-N, and available P and erosion intensity were found. Nutrient content per unit amount of eroded sediment decreased from the sheet to the shallow gully erosion zones, whereas total nutrient loss increased. Compared with topsoil, nutrients in eroded sediment were enriched, especially available P and NH4-N. The intensity of soil nutrient losses was also closely related to soil erosion intensity and pattern with the most severe soil erosion and nutrient loss occurring in the shallow gully channels on loessial hill slopes. These research findings will help to improve the understanding of the relation between accelerated erosion process after deforestation and soil quality degradation and to design better eco-environmental rehabilitation schemes for the Loess Plateau.

关键词： accelerated soil erosion deforestation erosion intensity Loess Plateau nutrient loss

体医融合对慢性心力衰竭患者心功能疗效及安全性评价

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中国医药指南 2025年第1期23卷 151-153页

作者：张燕夏普郑鑫三明市中西医结合医院心血管内科福建三明365001

目的探讨体医融合对慢性心力衰竭患者心功能的疗效及安全性评价。方法本研究为单中心、单盲、随机对照试验。纳入2023年6月1日至2024年6月1日就诊于三明市中西医结合医院的慢性心力衰竭患者80例作为研究对象,通过随机数字表法将其分为... 详细信息

目的探讨体医融合对慢性心力衰竭患者心功能的疗效及安全性评价。方法本研究为单中心、单盲、随机对照试验。纳入2023年6月1日至2024年6月1日就诊于三明市中西医结合医院的慢性心力衰竭患者80例作为研究对象,通过随机数字表法将其分为对照组(n=40)和研究组(n=40),对照组予基础治疗,研究组在基础治疗的基础上给予体医融合方案,疗程为12周,对比两组生活质量、运动耐力、心血管健康状况、心脏结构及生化检查。结果治疗后,研究组相较于对照组左心室射血分数(LVEF)、6 min步行距离(6MWD)更高,明尼苏达心衰生活质量量表(MLHFQ)、静息心率(RHR)、左心室舒张末期内径(LVEDD)、左心室收缩末期内径(LVESD)、左心房内径(LAD)、主动脉根部内径(AoD)、去甲肾上腺素(NA)、氨基末端脑利钠肽前体(NT-proBNP)更低(均P<0.05)。结论体医融合对慢性心力衰竭患者生活质量、心脏结构、理化指标均有良好的改善作用。

关键词：体医融合八段锦慢性心力衰竭心功能

Asymmetric catalytic anhydride openings via carbon-based nucleophiles

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Chinese Chemical Letters 2014年第1期25卷 1-8页

作者： Chen zheng fen-Er Chen Department of Chemistry Fudan University

The asymmetric desymmetrization of cyclic anhydrides via the addition of carbon-based nucleophiles has been the focus of considerable levels of interest because it leads to optically active products. Over the past 20 years, a variety of different catalytic asymmetric alkylation reactions have been developed for the desymmetrization of cyclic anhydrides using different metal reagents as nucleophiles and using chiral ligands. The purpose of this review is to provide an overview of significant developments in this field. ~ 2013 fen-Er Chen. published by Elsevier B.V. on behalf of Chinese Chemical Society. All rights reserved.

关键词： Cyclic anhydrides Carbon-based nucleophiles Chiral ligands Asymmetric catalysis Metal reagents

Dynamics of rotator chain with dissipative boundary

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Frontiers of physics 2014年第4期9卷 511-518页

作者： pu Ke Zhi-Gang zheng Department of Physics and the Beijing Hong Kong Singapore Joint Center for Nonlinear and Complex Systems (Beijing) Beijing Normal University Beijing 100875 China

We study the deternfinistic dynanfics of rotator chain with purely mechanical driving on the boundary by stability analysis and numerical sinmlation. Globally synchronous rotation, clustered synchronous rotation, and split synchronous rotation states are identified. In particular, we find that the single-peaked wariance distribution of angular momenta is the consequence of the deterministic dynamics. As a result, the operational definition of temperature used in the previous studies on rotator chain should be revisited.

关键词： rotator chain energy conduction

Measurement of the prompt neutron spectrum from thermalneutron-induced fission in U-235 using the recoil proton method

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Nuclear Science and Techniques 2019年第7期30卷 68-76页

作者： Tie He pu zheng Jun Xiao Key Laboratory of Radiation Physics and Technology Ministry of Education Institute of Nuclear Science and Technology Sichuan University Chengdu 610064 China Institute of Nuclear Physics and Chemistry China Academy of Engineering Physics Mianyang 621900 China

A measurement of the ^235U prompt fission neutron spectrum (PFNS) by the recoil proton method was performed at the Institute of Nuclear Physics and Chemistry, China. Details of the method, which include the calculation and validation of the response matrix, are presented. The PFNS for ^235U in the energy range 1–12 MeV, induced by thermal neutrons, was obtained. The measured spectrum in the low-energy region was in good agreement with previous work and the ENDF/B-VII library, except for minor differences. In the high-energy region, however, the relative height of the measured spectrum was greater, and an analysis of the experiment indicated uncertainties of 13% at 10 MeV and 24% at 12 MeV. Experimental results showed that the recoil proton method could be used to measure prompt fission neutron spectra. Some directions for future work are included.

关键词： Prompt fission neutron spectra Recoil proton method Response matrix U-235